In Program Manager Technical Advice PMTA 2018-008 the IRS discusses what are acceptable signatures for the business versions of Form 8453 (such as Form 8453C, 8453S, etc.).

In Notice 2007-79 the IRS allowed electronic return originators (EROs) to sign Form 8453, Form 8878, U.S. Individual Income Tax Declaration for an IRS e-file Return, Form 8878, IRS e-file Signature Authorization for Form 4868 or Form 2350; and Form 8879, IRS e-file Signature Authorization by specified alternative means. These means were:

Rubber stamp,
Mechanical device (such as signature pen), or
Computer software program.